Rhagoletis pomonella (Apple maggot) - Fact sheet


Apple maggot (Rhagoletis pomonella) is indigenous to eastern North America and has been a serious pest of apples in Canada for more than 100 years. The first record of this insect attacking apple fruit in Canada was in Ontario, in 1896. Apple maggot is now considered widespread throughout eastern Canada.

In 2006, this insect was found in Edmonton, Alberta and the Lower Mainland, Fraser Valley, and Vancouver Island in British Columbia (B.C.). These were the first detections of apple maggot in western Canada. In 2013, apple maggot was also confirmed in Prince George, B.C. The Okanagan, Similkameen and Creston Valleys in the southern interior of B.C. are the last major apple-growing areas in North America that are free of this pest.

Plant pest card - Apple maggot

Major hosts

The principal hosts of the apple maggot are apple (Malus spp.) and hawthorn (Crataegus spp.); sweet cherry (Prunus avium) and sour cherry (Prunus cerasus) are also significant hosts in two states of the U.S.A.

Minor hosts

Other hosts include serviceberries (Amelanchier spp.), cotoneasters (Cotoneaster spp.), red chokeberry (Aronia arbutifolia), black chokeberry (Aronia melanocarpa), Chickasaw plum (Prunus angustifolia), apricot (P. armeniaca), plum (P. domestica), peach (P. persica), Allegheny plum (P. umbellata), pear (Pyrus communis), Carolina rose (Rosa carolina) and Japanese rose (R. rugosa).


  • North America:
    • Canada: (NL, PEI, NB, NS, PQ, ON, MB, SK, AB, and portions of BC)
      • BC: Vancouver Island and the Regional Districts of: Mount Waddington, Comox-Strathcona, Powell River, Sunshine Coast, Greater Vancouver, Fraser Valley (except Electoral District Fraser Valley A) and Fraser-Fort George
    • USA: (AR, CA, CO, CT, DE, FL, GA, ID, IL, IN, IA, KS, ME, MD, MA, MI, MN, MS, NE, NH, NJ, NY, NC, ND, OH, OR, PA, RI, SC, SD, TX, UT, VT, VA, WA, WV, WI)
    • Mexico: (Chiapas, Coahuila, Mexico City, Guerrero, Hildalgo, Jalisco, Michoacan, Morelos, Nuevo Leon, Puebla, San Luis Potosi, Tlaxcala, Veracruz)


The apple maggot has only one generation a year. Females lay their eggs singly beneath the skin of the fruit. The larvae hatch 3 to 7 days later and tunnel into the fruit pulp. They complete their development within the fruit, taking anywhere from two weeks to several months to mature. Very rarely will larvae exit from hanging fruit.

Larvae generally remain in the fruit until after it drops to the ground. When larvae reach maturity they make an exit hole in the skin of the fruit and wriggle to the ground. Larval emergence from fruit may continue into early December. Larvae then enter the soil where pupation occurs. They enter the soil to a depth of 2 to 5 cm, usually beneath the host plant. Pupae stay dormant over winter, and they may persist in the soil for several years.

Adults emerge in late June or July and may feed on insect honeydew and bird dung, reaching sexual maturity 7 to 10 days after emergence. Mature, mated flies are attracted to good oviposition sites based on the spherical shape and scent of fruit. After mating, a single female fly is capable of laying more than 200 eggs in her lifetime. The average emergence date for all locations (east and west) is June 23. Adults usually die after 3 to 4 weeks but may live up to 40 days under field conditions.

Detection and identification


The apple maggot larva burrows in all directions through the flesh of apples feeding on the pulp and leaving brown channels. When a single fruit is infested with several larvae the pulp will be honeycombed with their burrows until it finally breaks down. Infested fruit are usually misshapen and dimpled looking (Figure 1). Oviposition punctures are surrounded by tissue discolouration and usually appear as black spots.


The adult is about 5 to 6 mm long, a little smaller than the housefly, easily recognizable by four irregular or zig-zag black bands on the wings (Figure 2). The body is generally black with a yellowish head and legs and greenish eyes. The male has three white bands on the abdomen and the female has four similar white bands and is considerably larger.

The eggs are elliptical, semi-opaque and creamy white, with both ends slightly yellow and more opaque, about 0.9 mm long and 0.23 mm wide. The legless larvae when fully grown are usually 6.5 to 8 mm in length and 1.5 to 2 mm in width at the widest point. The cream-coloured body consists of 11 apparent segments (Figure 4). The oval-shaped, yellow-brown in colour pupae are approximately 5 mm in length and 2.3 mm wide (Figure 5).

  • Figure 1 - infested fruit
  • Figure 2 - adult
  • Figure 3 - infested fruit
  • Figure 4 - larva
  • Figure 5 - pupae

Text: Plant Pest Surveillance Unit.
Photos : Agriculture and Agri-Food Canada, Research Branch, Ottawa